> First i tought most people would rather have bassy gear like Bose or Beats.

Most people buy after the brand name, not after sound quality - even though they sometimes follow what they think a certain brand promises in sound.
Few people are save from that - yourself (no disrespect to you, I'm sure you are a good listener) being not excempt either: Both Bose and Beats have made bass-light products! Yet the myth that "bose = bass" and of course "beats = bass" persists (not entirely unfounded eiher of course)

> A quick search showed me that the most sold earpiece was apparently the airpods (i couldn't fact-check), which have a treble bias.

Most likely not because of sound quality though, but because of the ease of use and also the brand name, as you said yourself:

> To me it only show that people react more to brand recognition and/or to the "fashion" element of their gear.

> But whether most people would rather want unbiased gear or not is left to be proven.

There's been quite a lot of research on that matter actually, plenty of controlled listening tests having been done with different ways of formulating essentially the same question: Do people prefer unbiased/"good"/neutral/uncolored sound, or have they gotten used to something else?
In general, most research (that I'm aware of) does in fact point towards the average person preferring what would be considered "good" sound (neutral, uncompressed, uncolored, ...) - as long as they're given the option.